Transmission device



Oct. 1, 1940. R. ERBAN TRANSMISSION DEVICE Original Filed Jan. 24, 1954a s 1 a m w a 4, M 2% W a d; E fi #1 w a 4 w m: a L i 4, M i 4 w v Mifiw N o I 7 m 5 k r 9 4 7 .fr 2 7 f m w W W If I W m 0 n w I i w n i 13 z/ (6) 7 L// 0 v} a 5 y w INVENTOR. fizz/2am ii'arz BY 1'54 7 KATTORNEYS? Patented Oct. 1, 1940 UNITED STATES PATENT OFFICETRANSDIISSION DEVICE Richard Erban, New York, N. Y., assignor to ErbanPatents Corporation, a corporation of New York 14 Claims.

The present invention was disclosed in my application Serial No.708,024, filed January 24, 1934, now United States Patent 2,148,857,patented February 28, 1939, in which division was required, and thepresent application is a division of my said prior application SerialNo. 708,92 l, and relates to torque loaders which are well-known in theart of friction transmission construction.

One of the problems in connection with variable speed frictiontransmissions is the establishment of a correct torque load on thedriving elements. Where the torque load is directly proportional to thetorque it may be correct fora definite speed ratio of transmission, andwhere the speed ratio of transmission changes the torque load will notbe correct. It will either be too little or too much, dependent on thechange. It is customary in designing torque loaders having a straightline characteristic to design the torque loader in such manner as toproduce sufficient pressure to take care of minimum conditions. Thenwhen the speed ratio is changed a situation will be reached wherein thepressure produced by the torque loader is far greater than is necessaryfor the particular conditions. The present invention is designed toproduce a variable ratio between the torque and the pressure produced sothat the torque loader will produce correct pressures on thetransmission elements throughout the range of speed ratios for which thetransmission is designed.

More specifically the torque loader comprising the present invention isone wherein the torque effective on the torque loader is transmittedthrough a leverage system whereby the torque effective upon the torqueloader elements may be increased or decreased dependent upon the designof the leverage system.

A still more specific characteristic of the present invention is atorque loader utilizing a leverage system through which the torque isoperative on the torque loader to produce the pressure, and wherein theeffective length of the arms of a lever may be varied. This variation ofthe effective lengths of the arms of the torque transmitting lever maybe accomplished by moving the pivot of the lever, whereby, if the leveris one of first class, the arm on one side of the pivot is shortened andthe arm on the other side of the pivot is lengthened the same amount.

The variation in this pivot point may be controlled in several ways, as,for example, a connection may be provided to the speed ratio changemechanism of the transmission so that when the speed ratio of thetransmission is changed the pivot point of the torque control lever isshifted and the torque effective on the torque loader elements ischanged in such manher as to produce the correct pressure for theparticular speed ratio setting of the transmission. This pivot point mayalso be controlled automatically by the transmission itself so as tomaintain a condition whereby the friction elements of the transmissiondo not slip relatively to each other. As, for example, the connectionsmay be such as to vary the pivot point to render the torque moreeffective on the torque loader when the creep between the transmissionelements exceeds a pre-determined amount.

Other and further characteristics of this invention will in part bepointed out in the specification hereinafter following, by reference tothe accompanying drawing wherein like characters are used to representlike parts throughout the several figures thereof.

Fig. l is a detail view illustrating a simple form of the presentinvention showing certain of the parts in section;

Fig. 2 is a view illustrating a modified form wherein the effectivelength of the leverage system is obtained by changing the effectiveradii of the lever on the system, and

Fig. 3 illustrates more fully a friction transmission embodying a formof the present invention, and shows certain of the parts in section.

Referring to Fig. 3, there is provided a drive shaft 15' to which issecured the roller support ll, on which are rotatably mounted aplurality of (non-adjustable) rollers 18. These move, on the one hand,on the race-ring l9, freely rotatable on shaft 15, and, on the otherhand, on a track of the race-ring 80, rotatably mounted on the drivenshaft 16. To the latter is secured the roller support 83 of theadjustable or tiltable rollers 82 which are mounted in a tiltable yoke'12, and the shaft 16 is rotated by the rotation of said support 83. Theadjustment of the rollers 82, for the purpose of varying the ratio oftransmission, can be effected by a means of wellknown constructioncomprising a collar 14 embracing a ball head 13 carried by a sleeve 84provided with a grooved collar 85, as indicated in Fig. 3. The rollers82 move, on the one hand, on the race ring BI] and, on the other hand,on the race ring 8|, which is so connected with the cylindrical casing86 by a groove 8| and stud Bl" so that these two parts are coupled torotate together. The race ring 8| is slightly axially movable so that bythe nut 81 it can be adjusted within narrow limits.

When the race-ring 19 is held against rotation and the drive-shaft l5 isrotated, the racering 89 is rotated by the friction rollers 18 atgreater speed than the shaft I5.

Now, if also the race-ring 8| is held against rotation theroller-support 83 and thereby also the driven shaft I5 are rotated,because the adjustable rollers 82 move like planetary gears. Dependingon the position of the rollers 82, the number of revolutions of theroller support 83 and of the shaft I6 varies. In the position of therollers 82 shown in Fig. 3, the number of revolutions is greatest, andsubstantially like the number of revolutions of the driving shaft 15. Ifthe rollers 82 are moved clockwise from the position shown, the numberof revolutions of shaft I6 becomes smaller. The moment of reaction ofthe gear occurs at two parts of the gear, that is to say, at therace-ring BI and the race-ring "E3. The moment of reaction of therace-ring l9 acts in the same direction as the driving moment, while themoment of reaction of the race-ring 8I is opposite to that direction.Now, if the gear runs with a ratio of transmission of 1:1, the twomoments of reaction are equally large, as will appear from Fig. 3, ifone considers that in that case the torques at the drive shaft l5 and atthe driven shaft I6 are equal to each other. However, since, as hasalready been stated, the moments of reaction of the rings 8| and 19 haveopposite direction, that is to say, tend to rotate said rings inopposite direction, the two moments of reaction balance each other, andthe total moment of reaction of the gear is nil. for the other positionsof the adjustable rollers 82 the moment of reaction of the race-ring 8ipredominates, so that there remains a positive total moment of reaction,the term positive being used for a reaction moment which has theopposite direction of the driving torque. Now, if the axial force ofpressure between the rollers 82 and the race-rings 88, 8i in everyposition of the rollers 82, has a value, which as nearly as possible,approaches the required value, the axial force exerted on the gear mustbe proportional to the torque of shaft I6. A control of the axial forceproportional to the torque of one of the two rings would result inconsiderably poorer conditions and a great excess of load, as has beenfully explained -in my copending application, Serial No. 679,843, filedon July 11, 1933. However, the sum of the torques of the race-rings 80,8|" can be used for adjustment, since said sum-must always be equal tothe torque of the roller carrier 83.

5 In the embodiment shown, the torque of the race-ring 89 is transmittedin a simple manner by means of a pressure device now to be described. Atthe right hand end of the cylindrical casing 86 there is secured acollar 88, which is provided with inclined faces 89. Another collar 90provided with similar inclined faces 9I bears, by means of balls 93,against the racering 79, and is so disposed that space is provided forthe balls 92 between the inclined faces 89, 9I. Now, if the collar 99 isprevented from rotation, but is allowed to move axially, there will beproduced in the pressure device 89, 92,

and 9i an axial force when the collar 88 rotates relatively to thecollar 90. The collar 90 can be held against rotation, for example, by ahollow shaft 94, which on its periphery carries-a brake-drum 95. Thesaid drum 95 can be prevented from rotation by a brake band 96. Thearrangement may be such that the drum 95 is prevented from rotation inone direction only, but is free to rotate in the other direction.

It has been shown supra that the correct axial force would be produced,if there were transmitted by means of a pressure device a torque,corresponding to the algebraic sum of the torques of the two race-rings80 and 8|. Now, the moment of reaction of the ring I9 is at a constantratio to the torque of the ring 80. It is decreased only in proportionto the sliding radius of the rollers I8 on the two rings 88 and I9 andmoreover, as has been stated above, has the opposite direction of thetorque of race-ring 8|. Therefore, the torque of the ring I9 would haveto be decreased in proportion to the transmission effected by therollers 78, and reversed so that together with the torque of the ring 8|it would result in the required total output. To this end there isprovided, in Fig. 3, rods 230 (one only being shown) which terminate inspherical ends 23I and 232. These spherical ends 23I and 232 are mountedin cylindrical openings 228 and 229 in the collars 88 and I9respectively. The rods 238 are mounted to slide through pivot balls 233that are mounted to rotate in slidable blocks 234 that are slidablymounted in guide-ways 236 provided in the collar 90. A suitableconnection, comprising a roller 238 and a pin 239, connects the slidableblocks 234 with a control collar 240 that is provided with a groove inwhich a control arm 24I extends. An opening 242 is provided in thecasing 86 to permit suitable movement for pin 239. It is to beunderstood that these parts are so connected as to be freely movable toaccomplish the movements required. The control arm 242 may extend from asleeve nut 244that is mounted on the screw threaded part 245 of thecontrol shaft 246 which may have one end resting in bearing frame member241. This control shaft 246 is also screw threaded at 248 to carry a.screw threaded sleeve 249 from which the speed control arm 258 extendsinto the speed ratio control collar 85. The screw threaded portions 245and 248 on the control shaft 246 are preferably of different pitch, andwith the part 245 having more threads to the inch than the part 248, sothat the sleeve 244 will have less linear movement than the sleeve 249for a revolution of the control shaft 246.

From the foregoing it will be observed that when the control shaft 246is rotated to oscillate the tiltable rollers 82 to change the speedratio that the control arm 242 shifts the pivot balls 233 along the rods230 and thus change the pivot points of these rods, to thereby changethe ef fective torque operating to cause the faces 89 and 9I to applypressure on the balls 92. This effective torque is so changed as toapply the proper torque load for each speed ratio of the transmission.

In Fig. 1 there is secured to the shaft I28 the ring I2I which on itsright hand side is provided with inclined faces I22. Between these andthe opposed inclined faces I25 provided on the ring I24 rotatably andaxially movably mounted on shaft I28 there are disposed balls I23. Thering I24 bears, by means of a set of balls I25, against large peripheralforce is effected.

provided with the same number of oppositely dis.-

.posed cavities I 29. The ring I'24,6along. its pelongitudinally movablymounted on rods I30. The

latter are journalled with their spherically shaped ends MI and I32 inthe. above said cavitiesIZB and IE9. All the balls I33 are so heldbyclaws I37 of an annular element I34 in a definite position that theyoccupy on. their rods R30, with respect to the spherically shaped headsIN and glththe same position. The annulus I34 is formed with a grooveI35 permitting it during the rotation to be displaced by a fork (notshown); This displacement can either take place together with theadjusting movement of the speed control, or may also be made to dependon other factors;

Instead of the transmission ratio being varied by a displacement of thefulcrum of the transdistance of the joints of the levers from the axisof the gear shaft, while the leverage remains unchanged. .Such aconstruction is shown in Fig. 2. On the shaft Mill is secured the ring MI which, by the pressure device M2, I43 and I45, is operativelyconnected withthe ring I M. The latter being loosely. mounted on theshaft Mil bears by means ofa series of balls I 46 against the ring It!which in turn bears against the race element M8. Also, the ring Hi7 andthe element M8 are loosely mounted on the shaft MEI. The ring Mil is.provided along its periphery with radial slots I ls. An equal number ofslots lil l is provided in the race element M8. Also the ring I44 isprovided with recesses I58 which are situated between the slots its andHit. A plurality of two-arm levers Itll, I52 and I59 are mounted withtheir intermediate ball-shaped pivots I51 in the recesses I53 of thering Hit in such a way I that they can both rock'in an axial plane andalso execute slight turning movements relative thereto. The two arms I5Iand I52 of each of the two-arm levers are equipped with rotatable ballsI50 and I53, adapted to move in the slots M9 and IE4 respectively. Eachtwo-arm lever is, moreover, provided with an arm I59, which by means ofa joint Hid permits the two-arm lever to be rocked about the fulcrumItl. The position of the two-arm levers shown in full lines in Fig. 10results in the greatest transmission between the race element m8 and thepressure device M2 M3 and M5, since the distance of the ball I53 fromthe axis of the gear is very small, so that a In the position of thetwo-arm lever shown by the broken lines, there results the smallestperipheral force and consequently, the smallest axial force produced bythe pressure device. It is understood, of course, that when a pluralityof two-arm 1evers are used, all the joints it!) must be displacedsimultaneously.

Insmad of the above described mechanical transmissions (levers, toothedsectors, etc.) there can be used of course, also other types oftransmissions, e. g. hydraulic transmissions, without any departure fromthe principle of the invention herein involved. Therefore, theconstructions herein described and shown are only to be considered asillustrations of the fundamental arrangements, since it is impossible todescribe all the combinations and uses of all the equivalenttransmission devices at present known.

What I claim is:

1. In a device of the class described, two relatively rotatable members,a pressure device operable to produce axial-pressure in response to thetorque transmitted by the said two members, means including a lever tomultiply the axial pressure produced by the said pressure device at agiven torque, the ratio of 1nultiplication of said lever being variable,and means to vary said ratio of multiplication.

1 3; In a device of the class described, two relatively rotatablemembers, a pressure device operable to produce axial pressure inresponse to the torque transmitted by the said two members,

and a lever system having a variable fulcrum to multiply the axialpressure in predetermined ratios to the torque being transmitteddepending upon the position of the fulcrum.

4. In a device of the class described, two relatively rotatable members,a pressure device operable to pro duos axial pressure in response to thetorque transmitted by the said two members, a shaft, and a leveradjustable to different angles to the said shaft to multiply the axialpressure in predetermined ratios to the torque being transmitteddepending upon the adjusted angle. I

Y 5.'In a device of the class described, two relatively rotatablemembers, a pressure device op: erable to produce axial pressure inresponse to the torque transmitted by the two said members, slidablemeans to modify in predetermined and adjustable ratios the axialpressure produced by the said pressure device at a given torque, andmeans capable of operation at all times to effect a change of saidratios.

6. In combination with a power transmission system in which power istransmitted from a driving to a driven element by the adhesive drivingcontact of races with rollers therebetween, a pressure device formaintaining the adhesive driving contact of the rollers with the races,means for receiving and modifying at least one of the torques passingthrough the system according to a predetermined law and for applying.said modified torques to said pressure device,

said modification taking place according to a predetermined law, andcontrol means being adjustable to change said law.

7. In combination with a power transmission system in which power istransmitted from a driving to a driven element by the adhesive drivingcontact of races with rollers therebetween, a pressure device formaintaining the adhesive driving contact of the rollers with the races,and means for receiving at least one of the torques passing through thesystem, said means comprising a lever having a movable fulcrum formultiplying at a variable ratio the received torque and applying thesame in multiplied form to said pressure device.

8. In combination with a power transmission system in which power istransmitted from a driving to a driven element by the adhesive drivingcontact of races with rollers therebetween, a pressure device formaintaining the ad.-

hesive driving contact of the rollers with the races, means forreceiving a torque passing through the system, said means comprising amechanism for modifying the torque in a predetermined ratio and forapplying it in said modified form to said pressure device, and meansoperable to vary the said predetermined ratio.

9. In combination with a power transmission system in which power istransmitted from a driving to a driven element by the adhesive drivingcontact of races with rollers therebetween, a pressure device formaintaining the adhesive driving contact of the rollers with the races,means for receiving a plurality of torques passing through the system,said means comprising a lever having a movable fulcrum for combining andmodifying said torques, and applying the same in such combined andmodified form to said pressure device, and means for changing theeffective leverage of said first mentioned means.

10. In a device of the class described, two relatively rotating members,a third rotatable member intermediate the two members, a pressure devicebetween the said intermediate member and one of the said two rotatablemembers, and a lever fulcrumed on the said intermediate member havingits ends operatively connected to each of the two said rotatablemembers, the lever arms of the said lever being such that the axialpressure produced by the said pressure device will be increased at agiven torque, the fulcrum of the said intermediate member beingadjustable to vary the lever arms of the said lever so as to increasethe axial pressure in predetermined ratios to a given torque.

11. In a device of the class described, two relatively rotatablemembers, a third rotatable member intermediate the two said members, apressure device between the said intermediate member and one of the saidtwo rotatable members, and a lever fulcrumed on the said intermediatemember having its ends operatively connected to each of the two saidrotatable members, the lever arms of the said lever being such that theaxial pressure produced by the said pressure device will be increased ata given torque, said lever being mounted so that it may be adjustablytilted on its fulcrum on the said intermediate member so as to increasethe axial pressure in predetermined ratios to a given torque.

12. In a device of the class described, two axial relatively rotatablemembers, a pressure device operable to produce axial pressure inresponse to the torque transmitted by the said two members, meansincluding a lever having a shift able fulcrum to modify the axialpressure produced by the said pressure device.

13. In a variable speed friction transmission, two coaxial relativelyrotatable members, a pressure device operable to produce axial pressurein response to the torque transmitted by the said two members, meansincluding a lever to modify the axial pressure produced by the saidpressure device, a movable fulcrum for said lever, and

means to change the speed ratio of said transmission and to move saidfulcrum.

14. In a device of the class described, two 00- axial relativelyrotatable members, a pressure device operable to produce axial pressurein response to the torque transmitted by the said two members, and meansincluding a lever to multiply the axial pressure produced by the saidpressure device, the respective points of application of said levermeans to said two members being axially displaced and at difierentradial distances from the axis of rotation of said members.

RICHARD ERBAN.

